It has been said time and again on these forums that it is not possible to backlight an eInk screen. When a friend of mine told me he was considering a Samsung Alias2, with an eInk keypad that changes for different functions I asked about how it would be used in the dark, which he often needs to do as a plumber working in basements and cramped spaces. He kindly informed me that it was backlit, and pointed me to a video (http://www.engadget.com/2009/05/08/v...pad-in-action/).

Looking at the vid, it does appear to be backlit, yet I thought people had made it clear on these forums that this was not possible. Anyone know what Samsung is doing differently?

I'd always thought that back-lighting required a transmissive display (i.e. one that relied on light passing through it to generate the image), and that e-ink was a reflective display, i.e. that light was reflected from it. Whilst being a reflective display doesn't preclude lighting, I'd assumed that it would not then be a back-lit, but instead a front-lit display (e.g. as the Sony accessory does). Or have I misunderstood something (decidedly possible!)?

It appears from the web pages I looked at that they are talking about the keypad being e-ink or e-paper (making the keys changeable), not the screen part. The screen is in color, so probably not e-ink.

It is not possible to backlight an e-INK screen as the light cannot show through since the ink is not transparent. However other e-Paper technologies might be able to support a transparent screen that could be backlit. You would have to study the various techniques, one is bi-stable LCD.

Well, I still don't get it. They are definitely claiming it is eInk, or as they put it: "Magic Keypad with E–Ink Technology." I suppose it could be an illuminated film as =X= suggests. Looks nice. Certainly brings up some interesting possibilities.